Eliot is offering his view of modern civilization. Note the many ugly references to grim and emptiness: "withered leaves," "grimy scraps," "broken blinds and chimney pots," "stale smells of beer," and "dingy shades." Setting the poem in winter, furthermore, suggests despair and loneliness despite the urban location.
Following World War I, the world view of many poets like Eliot was that modern society was in a state of decline and decay. He has chosen to write about a city in such a condition with images of cigarettes, pollution, and beer to suggest urban squalor without any sense of hope.
In addition to Cybil's comments, you might also want to consider the place of the "smell of steaks," the cigarettes, the beer and the coffee stand in the poem. Think about why Eliot includes these references amongst "the grimy scraps/of withered leaves" and "muddy feet."